Toronto police are conducting another helicopter scan of two city parks in the continuing search for missing teen Mariam Makhniashvili.

A previous aerial search was conducted on September 25th -- more than a week after the now 18-year-old student went missing .

The only solid clue in the case to date is Mariam's backpack, which was found with some school books in a parking lot on October 8th.

About three weeks later, police seized several computers from two libraries to see who Mariam contacted and what websites she visited.